The worker, who is not being identified, was infected on some dates he or she was working, including from July 25 through Aug. 11, said Dr. Lynne Saddler, the department's district director.

She said there may have been "hundreds" of people who were at the Syndicate during that time.

“We get concerned when a food-service worker that’s handling food that’s not going to be cooked has hepatitis A," Saddler said. "We always will err on the side of caution."

In addition to vaccination, Saddler had this suggestion: "Be fastidious in washing your hands, even at home," before eating or preparing food and after diaper changes and restroom use.

She noted that, even if people "say they are always washing their hands," it's best to take precautions.

While the health department has recorded 56 cases since January, most of them came in July, with 22 new cases. So far in August, there are have been 16.

This electron micrograph shows numerous hepatitis virions, strain unknown, which are the agents for viral hepatitis. The CDC describes viral hepatitis as an important public health problem because it causes serious illness, it affects millions, and it has a close connection with HIV. There are five identified types of viral hepatitis and each one is caused by a different virus. In the United States, hepatitis A, hepatitis B and hepatitis C are the most common types.(Photo: Public Health Image Library/Centers for Disease Control and Prevention)

Hepatitis A can be spread through food or drinks that are contaminated with the virus. According to Foodsafety.gov, the virus typically is spread at restaurants in uncooked foods and cooked foods that are not reheated after contact with an infected food handler, raw produce or raw or undercooked shellfish from contaminated waters.

"Anyone who consumed food or drink at Newport Syndicate during the stated time period is advised to get a hepatitis A vaccination," the health department said.

Two weeks ago, the Hamilton County Public Health Department noted that county jail inmates were getting vaccinated for hepatitis A after four inmates were diagnosed with the virus.

The two Kentucky outbreaks are occurring even though hepatitis A rates have declined more than 95 percent since 1995, when the vaccine first became available, the federal Centers for Disease Control and Prevention says on its website.

In 2016, there were an estimated 4,000 hepatitis A cases in the United States. Cases related to food were relatively rare. There were three outbreaks linked to food that year, resulting in 457 illnesses, 141 hospitalizations and two deaths, according to the CDC's National Outbreak Reporting System.

The incubation period for the virus normally is 28 days. Symptoms appear in two to seven weeks. The symptoms in adults are fatigue, low appetite, stomach pain, nausea, and jaundice, but they usually resolve within 2 months of infection. Most children younger than 6 do not have symptoms or have an unrecognized infection.

Most people who get hepatitis A recover completely and have no lasting liver damage. The rare cases where hepatitis A causes liver failure and death tends to be in people older than 50 and in people with other liver diseases.

Hepatitis A vaccine.(Photo: Provided)

Unlike other forms of hepatitis, hepatitis A does not result in chronic infection. Antibodies produced in response to hepatitis A infection last for life and protect against reinfection. The best way to prevent hepatitis A infection is to get vaccinated, the CDC says.